Motor vehicle driving mechanism



Jan. 9, 1951 B. W. KEESE MOTOR VEHICLE DRIVING MECHANISM 6 Sheets-Sheet l Filed March l, 1944 Jan. 9, 1951 B. w. KEEsE MOTOR VEHICLE DRIVING MECHANISM 6 Sheets-Sheet 2 Filed March l, 1944 Jan. 9, 1951 B. w. KEESE 2,537,060

MOTOR VEHICLE DRIVING MECHANISM Filed March l, 1944 6 Sheets-Sheet 3 eery mese MOTOR VEHICLE DRIVING MECHANISM 6 Sheets-Sheet 4 Filed March l, 1944 www.:

Jan. 9,\ 1951 B w, KEESE 2,537,060

MOTOR VEHICLE DRIVING MECHANISM Filed March 1, 1944 6 Sheets-Sheet 5 f //a I im Q//M MKS Jan. 9, 1951 B. w. KEESE MOTOR VEHICLE DRIVING MECHANISM Filed March l, 1944 6 ,Sheets-Sheet 6 Patented Jan. 9, 1951 MOTOR VEHICLE DRIVING MECHANISM Beverly W. Keese, Oshkosh, Wis., assignor to The Timken-Detroit Axle Company, Detroit, Mich.,

a corporation of Ohio Application March 1, 1944, Serial No. 524,600

(Cl. 'I4-700) Claims.

This invention relates to motor vehicle driving mechanism and more particularly to driving mechanism for farm tractors and similar vehicles where the relative arrangement or location of the several driving units with respect to each other and the driven wheels of the Vehicle is a factor of major importance in the efiicient operation of the vehicle to economically and prontably accomplish the purposes for which the particular vehicle is designed.

Heretofore, in farm tractor design the engine and drive gearing, in` some cases, was arranged at a comparatively high elevation above the wheel centers for clearance of the crop rows, plows and cultivating tools. The transmission and intermediate reduction gearing were above the wheel centers, while the iinal drive gearing was in the wheels. This arrangement has the objection of low power output to the driven Wheels and consequently low operating speed of the vehicle.A

In other suggested designs the power output shaft of the transmission was located below the wheel axle centers but the relative arrangement of the diiferential and speed reduction units and the driving connection with the transmission had the disadvantage of relatively high power losses,

vdecreased operating eiliciency and heavy maintenance expense resulting from severe mechanical stresses to which the relatively movable parts are necessarily subjected in a mechanism of this kind.

It is accordingly a major object of the present invention to eliminate the above noted serious objections to prior tractor drive designs and to provide a simple, rugged and compactly associated arrangement of the several power transmitting or driving units between the engine clutch shaft and the wheel axles ofthe vehicle. To this end I propose to arrange the differential and iinal gear reduction driving unit between the wheel axles, and the variable speed transmission unit with the output shaft axis of the latter unit and the differential major shaft axis preferably disposed in a common horizontal plane which is below the vehicle Wheel axle centers. In this way a low centerof gravity of the transmission and differential units is obtained, and, by eliminating the final drive gearing in the vehiclewheels, large diameter wheels may be employed to insure adequate implement and crop row clearance, as well as better traction.

Another object of my invention resides in the provision of a one-piece housing structure for the transmission and differential which may be conveniently installed as a single unit between the reduction gear housing and clutch and pulley drive gear housing, with means for uniting said housing structures to provide, in effect, a continuous, longitudinally rigid support for the several power transmitting and driving mechanisms.

A further object is to provide improved means for coupling the rear end of the clutch driven shaft to the forward end of the transmission power input shaft so that the latter shaft may be operatively mounted in only two bearings.

It is also an object of the invention to provide an improved differential construction and mounting, with direct driving connections between the differential side gears and final speed reducing gears on the respective Wheel axles.

An additional object is to devise improved means for independently or simultaneously applying braking torque to the differential side gears and, in one embodiment thereof, to providev easily and quickly operable means for rigidly' locking the brake drums in connected relation with said gears and simultaneously adjusting the differential shaft bearings.

A still further object of the invention resides in the provision of actuating means for an accessory unit, mounted on the pulley drive gear housing, and means for manually controlling the transmission of power to said actuating means from the coupling connection between the input l shaft of the transmission and the clutch shaft.

Among other important objects of the invention reference may be made to an improved gear selector means for effectively locking the idle gears against axial movement on the power input shaft, and a common means for the adjustment of an end bearing for the transmission input shaft and for yieldably resisting axial movement of the variable speed and reverse gears in one direction along said shaft.

Further objects of the present invention will become apparent from the following description, when considered in connection with the accompanying drawings and the appended claims.

In the drawings, which illustrate one' simple and practical embodiment ofthe invention:

Figure 1 is a sectional view in a vertical plane .substantially on the longitudinal center line of the vehicle showing a preferred relative arrangement of the cooperative units of my Vehicle driving mechanism; l Figure 2 is a horizontal sectional view taken substantially on the line 2--2 of Figure 1;

Figure 3 is a vertical transverse section taken substantially on the line 3-3 of Figure 1;

Figure 4 is a vertical sectional view taken substantially on the line 4-'4 of Figure 2;

Figure 5 is a transverse sectional view taken substantially on the line 5--5 of Figure 2;

Figure 6 is a detail front elevation of the housing for an accessory operating unit;

Figure '1 is a detail sectional view taken substantlally on the line 1--1 of Figure 3, illustrating the mounting of the reverse gear clutch;

Figure 8 is a fragmentary horizontal section taken on the line 8-8 of Figure 1;

Figure 9 is a horizontal section taken on the line 9-9 of Figure 3;

Figure 10 is a detail vertical section taken on the line IIl-I of Figure 3;

Figure 11 is a vertical sectional view through one side of the reduction gear housing and one of the axle casings, illustrating the mounting of the axle and one method of securing the wheel hub thereon;

Figure 12 is a detail horizontal section on an enlarged scale of the accessory operating means shown in Figure 2 and the gear shift mechanism therefor;

Figure 13 is an enlarged vertical sectional view of the outer end of the power take-off shaft housing; and

Figure 14 is a detail fragmentary perspective view of one of the shifter forks of the gear selector mechanism.

Like reference characters indicate similar parts throughout the several views.

Referring to the drawings in greater detail, in the embodiment of my invention selected for purposes of illustration, the vehicle driving mechanism preferably comprises three primary units, viz., a clutch housing and power take-off unit A; a combined transmission and differential unit B;

and the final drive or speed reduction and axle bearing unit C. By reason of this division of the mechanism into structurally independent units their assembly into an accurately :zo-related, cooperatively functioning power transmission system is greatly facilitated. These units will now be more specifically described in order.

The un t A embodies a bell housing section I0 for the clutch operating mechanism and a rear powel` take-off gear compartment II'dened by forming the casting with vertical and horizontal partition Walls I2 and I3, respectively, which are integral with the top, side and front end Walls of the casting.

The driving mechan'sm to be later described is operatively connected with the power shaft of the engine or motor by the usual driven clutch shaft I4. The rear end of this shaft is rotatively supported by a suitable type of anti-friction bearing I mounted in the fiont Wall I2 of the compartment I I and projects for a short distance into said compartment. This projecting end of the shaft is form-ed with the splines I5 for a purpose which will be presently described,

The shaft I4 is further supported by a long .bearing sleeve I1 having a flanged end I8 securely bolted to the front-face of the Wall I2, as indicated at I9. This sleeve is formed with the arm 20 extending radially from one side thereof, said arm being provided with a pivot stud 2| for the clutch throw-out lever 22. This lever when operated by the connecting rod 23 from the operators clutch lever not shown) actuates the clutch throw-out collar 24 slidably supported on the bearing sleeve I1.

The forward end of the shaft I4 is normally connected with the motor shaft by a suitable type of flywheel clutch, the shaft end being supported in the flywheel 25 by the pilot bearing 29. The top wall of the bell housing section III is provided with an opening 21 for convenient access to the clutch mechanism, said opening being normally closed by the cover plate 28.

One side wall of the compartment II is provided with an opening to receive the large diameter end section 30 of a load bearing casing 29 for the shaft 3I, said casing and shaft extending from the side of the unit A at substantially right angles to the vehicle center line. Preferably, the opening through the wall of compartment II is defined by the boss 32 thereon, .which affords extensive supporting contact for the end 30 o! casing 29, and a. flange 33 on the casing wall is securely bolted to said boss, as at 34.

The shaft 3| at its inn-er end is rotatably supported upon the part 30 of the shaft casing by a suitable type of anti-friction roller bearing 35, said shaft end, at the inner side of the bearing, having a bevel pinion 36 keyed or otherwise securely fixed thereto. At its outer end the shaft 3i is also supported in the anti-friction bearing 31 mounted in the enlarged outer end 38 of the casing 29. The shaft end projects beyond the casing and has a belt driving pulley 39 or other equivalent power transmitting element fixed thereto. The hub portion 40 of said pulley has contact at its inner end with the inner race of bearing 31 and by adjusting the nut 4I on the reduced threaded end of shaft 3| the bearings 35 and 31 are properly adjusted and pinion 36 positioned in compartment II for accurate mating engagement; with the teeth of a driving pinion, as will be later described. The outer end of the part 38 of the shaft casing is closed by a conventional type of oil seal 42.

Above the bearing 35 the side wall of compartment II is formed with an internally projecting, upwardly inclined flange 43, providing a receiving trough for oil during operation of the gearing and by which such oil is directed by gravity through the downwardly inclined duct or passage 44 to the space between the shaft 3i4 and casing 29 at a point outwardly spaced from the casing attaching ilange. One section of this duct is formed through the boss 32 and the other section thereof extends through an integral connection between the casing wall and attaching ange 33. The outer end 38 of the shaft casing is formed at its lower side with a relatively thick wall section having the internal duct or passage 45 opening at its ends into the casing on opposite sides of the bearing 31. In this manner an adequate supply of lubricating oil to the bearings 35 and 31 is assured.

At the lower side of gear compartment II the casting I0 of unit A is cored out as indicated at 46 to lighten the structure.

The unit B of the assembly includes a housing structure 41 for the variable speed transmission and differential mechanisms. This housing is preferably in the form of a one-piece casting internally divided by the vertical wall 48 into the transmission gearing compartment 49 and the differential gearing compartment 50. The bottom wall 5I of the housing structure is downwardly inclined from front to rear for the gravity flow of lubricatingoil from compartment 49 into com partment 50 through the opening 52 in the lower end of wall 48.

The front end wall 53 of the housing structure 41 is adapted to be securely bolted vto the rear end wall flange 64 of the clutch and power take-oi! housing structure I8, as shown at 55.

The power input shaft 56 of the' transmission is rotatabhr supported at one of its ends by a con- 'ventional type of anti-friction bearing 51 mounted in the housing wall 48. Between this bearing and a similar supporting bearing 58 in the housing end wall 53 the'input shaft is formed with longitudinally extending peripheral splines 59 to coact with complementary internal splines of the speed selector gear clusters 68 and 6|,v respectively, whereby the latter have unitary rotation with said shaft while being freely shiftable'axially thereof, as will be presently explained. The bearing 58 abuts an annular shoulder 62 on the rear wall of the housing structure |8 and closes an opening 63 therein through which the frontv end section 64 of the input shaft 56 extends into the compartment in axial alignment with the clutch shaft I4. The opening 63 accommodates the outer end of a bevel driving pinion 65, keyed or otherwise fixed to the shaft section 64 and held in abutting engagement with the inner race ring of bearing 58 by the snap ring 66 seated in an annular grove in said shaft at the inner end of the pinion. This pinion has driving engagement with the pinion 36 on the inner end of powertake-off shaft 3|.

The forward end of the input shaft section 64 is also splined as at 61, said splines mating with the splines I6 on the rear end of the clutch shaft I4 for coaction with the internal splines of a coupling sleeve 68, whereby said shafts are connected for unitary rotation. One end of said sleeve abuts the inner race ring of clutch shaft bearing |5 and the other end thereof is engaged by the snap ring 69 seated in a groove in shaft section 64 to prevent longitudinal movement of the coupling sleeve. The latter end of said sleeve has a driving pinion 18 integrally formed therewith which drives actuating means for an hydraulic lift pump. as will be later described.

Below and slightly to one side of a vertical plane which includes the axis of the input shaft 56 the power output shaft 1| of the transmission is supported at its opposite ends `upon housing walls 48 and 53 by anti-friction roller bearings 12 and 12', respectively, of well known type, the axis of said output shaft being substantially coincident with the longitudinal center line of the vehicle. Between said bearings the change speed gears 14, 15, 16 and 11 are keyed or otherwise seourely Xed on the shaft 1|, said gears transmitting first, second. third and fourth driving speeds, respectively, to the power output shaft 1 I from the input shaft 56. Reverse rotation is also transmitted to said output shaft through the gear 14 in the manner to be presently explained. Preferably these gears are arranged in pairs, the gears in each pair having hub portions 18 and 19, respectively, laterally extending on one side of the plane of the respective gears for abutting contact with each other. Thus, the engaged hubs 18 of the first and second speed gears 14 and 15 prevent movement of said gears toward each other while the engaged hubs 19 of the third and fourth speed gears 16 and 11 servea similar purpose with respect to the latter gears. The two pairs of gears are held in longitudinally spaced apart relation on the output shaft 1| by the spacing collar 1|', surrounding said shaft between and in abutting contact with the hubs of the second and third speed gears and 16, respectively.

Between the gear 11 and bearing 12 a crimped spring washer 88 surrounds the output shaft 1I and serves the double purpose of an adjusting means for the bearing and also to resist any tendency ofy the driven change-speed gears to move" longitudinally in one direction along the output shaft.

At its opposite end the output shaft 1| has a reduced threaded portion to receive the adjusting nut 13' for the bearings. Between the inner side of bearing 12 and the hub of gear 14 a spacing washer 14' is interposed. The adjusting nut 13', when operated. finally adjusts the bearings 12 and 12 at both ends of the output shaft and is received in the recess or cavity 54 in the rear end wall of the housing structure I8 lwhen the housing 41 is assembled therewith. The inner race ring of bearing 12 is engaged by one end of the bevel gear 13 integrally formed on the rear end of input shaft 1|, and drives the differential mechanism in compartment 58, as will be later described.

The gear cluster 68 on the transmission input shaft 56 includes the integrally formed first and second speed gears 8| and 82, respectively. and grooved collar 83, receiving the arms of the shifting fork 84 by which the cluster 68 is shifted along the input shaft to selectively mesh the gears 8| and 82 thereof with the gears 14 and 15. respectively, on the output shaft 1|. The other gear cluster 6| includes the integrally formed gears 85 and 86 and grooved collar 81 which receives the arms of shifting fork 818 by which the gear cluster is shifted to selectively mesh the gears 85 and 86 thereof with the gears 16 and 11, respectively, on the output shaft 1|.

At one side of the input shaft 56 and slightly above the axis thereof a relatively short idler shaft 89 is suitably fixed at one end in the front end wall-53 of the transmission compartment 49 and at its other end in a bracket lug 98 formed on a side wall of said compartment. On this shaft the reverse gear cluster 9| is slidably and rotatably mounted. This cluster includes the integrally formedV gear elements 9'2 and 93, respectively, and between said elements the annular groove 94 is formed to receive the arms of the shifting fork 95. Reverse rotation is transmitted to the output shaft 1| in the usual manner by shifting the gear cluster in one direction on the shaft 89 from its normal idle position to mesh the gears 92 and 93 thereof lwith gear 14 on the output shaft 1| and gear 6| on the input shaft 56, respectivey.

The opening 96 in the top wall of the transmission compartment 49 is closed by a bonnet type cover casting 91 which houses the selector mechanism and upon which the usual shift lever 98 therefor is mounted. In the following detail description of this mechanism reference is made more particularly to Figures 1, 3, 8, 9, and 10 of drawings.

The base of the casting 91 is provided, at the front side thereof, with three horizontal openings 99 and at its rear side with three internally opening horizontal bores |88, in alignment with the respective openings 99. Shifter fork guide rods |8I, |82 and |83 for the forks 84, 88 and 95, respectively, are supported at their opposite ends in these bores and openings of the casting 91, the latter end of each rod having a transverse opening, registering with a vertical opening in the casting base, to receive a pin |84 which locks the rod against rotative or longitudinal movement. Suitable closures 89' may be applied to the outer ends of the openings 99.

The rods |8|, |82 and |83 are parallel to each other and to the input shaft 56 of the transmission. Each of the gear shifting forks is formed with a sleeve at its upper end freely slidable on one of said guide rods. Each sleeve is provided at its upper side Iwith a laterally off-set arm |06 having a vertically slotted or bifurcated end |01, the opposite sides of which are suitably spaced apart longitudinally of the guide rod to receive the lower end of the shift lever 98 therebetween. At each side of the slot the arm |08 is formed with an upwardly extending lug |08 for a purpose which will be presently explained. y

Above the fork guiding rods the selector gate |09 is mounted in the bonnet casting 91. Preferably this gate is formed from a heavy metal stamping'and comprises a rectangular plate having its opposite ends formed to provide parallel sleeves I I0 slidably engaged on the rods I, disposed at right angles to the fork guiding rods. Any suitable means may be employed for xedly mounting the rods at their ends in the opposite side walls of the casting 91. The selector gate is provided with an elongated slot ||2 in parellel relation to the fork guiding rods and centrally thereof, and at each side, the metal locking ribs II3 are welded or otherwise secured to the lower face of the gate. These ribs extend from the slot ||2 to th'e opposite side edges of the gate. Upon eachof the rods III between one end of the sleeve ||0 and the opposed wall of the casting 91 a spring I I4 is interposed. These springs bias the selector gate |09 and lever 98 to a normal position and yieldingly resist movement of the gate and the lower end -of shift lever 98 in one direction to connect said lever with the reverse gear shifting fork 88.

From the above description the' operation of the gear selector mechanism may be readily understood.-A The shift lever 98 has the usual universal, balll-and-socket mounting in the upper end of the bonnet casting 91, as indicated at I I5, and extends downwardly therefrom through the slot I|2 in the selector gate |09. Below said gate the lower end II6 of the lever, in the normal upright position thereof, is disposed within the slotted end of the arm |06 of shifter fork 88 for the third and fourth speed gears, as seen in Figure 3. To shift into first or second speed the upper end of lever 98 is moved to the right and the lower end thereof, bearing against one side edge of the slot ||2, moves selector gate |09 to the left on rods III and is connected with the slotted arm |06 of shifting fork 84, as shown in broken lines in Figure 3. In this movement of the selector gate one of the ribs ||3 thereon is positioned between the lugs |08 on arms |06 of forks 88 and 95, thus locking the latter forks, which shift the third and fourth speed and reverse gears, against shifting movement. A rearward movement of the upper end of lever 98 will now shift the fork 84, sliding gear cluster 60 forwardly and connecting gear 8| thereof with gear 14 on the transmission output shaft for rst speed drive. By moving the upper end of the lever forwardly said gears are disconnected and by continued movement of the lever gear 82 is then connected with the second speed gear 15 on the power output shaft. In these gear shifting movements of the lever its lower end moves longitudinally in slot I I2 of the selector gate |09.

Upon shifting gear cluster 60 to a neutral position and returning lever 98 to an upright position the latter is again connected with fork 88. A rearward movement of said lever now shifts gear cluster 6| on the input shaft 56 to connect its gear 85 with gear 16 on the output shaft 1| for third speed drive, while a forward movement of said lever connects gear 86 with gear 11 for fourth speed drive. The forks 84 and 85 are locked against movement by the ribs I|8 on the selector gate, respectively, positioned between the lugs |08 of the latter forks.

To reverse the rotation of transmission output shaft 1I the upper end of lever 98 (Figure 3) is first moved to the left. The selector gate |88 is thereby moved to the right against the resistance of springs I |4 and the lower end of said lever is connected with the arm |06 of fork 85. A forward movement of the upper end of lever 98 now shifts reverse gear cluster 9| rearwardly, connecting gear 92 thereof with gear 14 on the output shaft 1I and gear 93 with gear 8| on f the input shaft 56. Thus the direction of rotation of the power output shaft is reversed with respect to the input shaft of the transmission. In this position of the gear shift lever shifting forks 84 and 88 are respectively locked by one of the ribs II3 engaged between spaced lugs |08 of said forks.

If desired, the bonnet casting 91 may be provided with suitable externally formed bearing means ||1 for the clutch and brake operating shafts.

The differential drive mechanism for the vehicle wheels is contained in housing compartment 50 of the unit B and includes a transversely positioned main shaft ||8, preferably located with its axis disposed in a common horizontal plane with the axis of the transmission power output shaft 1I. The shaft ||8 has a plurality of longitudinally extending oil distributing grooves I I9 formed in its periphery and a spider |20 is pressed upon the central portion of said shaft, the metal thereof interlocking in said grooves and establishing a securely xed connection between the shaft and spider. The spider |20 has a hub portion |2I, a rim portion |22 and a connecting web portion |23. The latter at diametrically opposite sides of the shaft ||8 is provided with openings |24 therein to accommodate the bevel pinions |25 rotatably mounted upon radially disposed pins |26, the ends of which are engaged in aligned openings in the hub and rim portions of the spider. The peripheral face of the spider rim |22 is provided with an annular groove |21 and each of the pins |26 with a registering groove I28 in its outer end face to receive a locking ring |29, whereby said pins are held against rotative or longitudinal movement in the spider. The unloaded portion of each pin |26, at diametrically opposite points, has longitudinally flattened surfaces |30 spaced from the pinions I25 to provide oil circulating passages and the end faces of the spider hub I2| are provided with grooves I3I diametrically therrof for a similar purpose. Also grooves |32 in the spider rim connect with the passages formed by the flattened surfaces |30.

The spider rim |22, at one side thereof, has an integrally formed annular flange |33 to which the ring gear |34 is securely bolted, as at |35. The teeth of this ring gear are in meshed engagement with the teeth of the bevel gear 13 so that unitary rotation is transmitted from the power output shaft 1I to the spider |20 and pinions |25 thereon, in a vertical plane about the axis of the transverse shaft |I8.

At each side of the spider |20 a sleeve |36 is loosely engaged upon the shaft I|8 for rotation relative thereto. Each of these sleeves at its inner end has a bevel gear |31 integrally formed therewith, said gears respectively meshing with the pinions |25 at opposite sides thereof. Adjacent to each gear '|31 elongated spur gear teeth |36 are formed on the periphery of the respective sleeves |36 for engagement with nal drive gears on the vehicle wheel axles, as will be presently explained. Oil is supplied, through one or more radial openings |39 in the sleeves. to the grooves ||3 in shaft ||6.

Shaft ||8 and sleeves |36 are rotatably supported n the opposite side walls of housing compartment 50 by the roller bearings |40. The inner race rings of these bearings have a driving fit on the respective sleeves and are engaged by the outer sides of the spur gears |38 thereon. At the outer side of each bearing |40 an annular member |4| is engaged with the outer bearing ring and secured to the housing wall by bolts |42. Between this member and the outer face of said wall, one or more bearing adjusting shims |43 are interposed.

Each member |4| is internally formed to receive an annular oil seal |44 of conventional type, which surrounds the inner end portion of the hub |46 of a brake drum |45 fixed upon the outer end of the respective sleeves |36. Each of said sleeves extends beyond the corresponding end of shaft 6 and is externally provided with longitudinally extending grooves or slots to receive the tapered splines |41 on the hub wall of drum |45. The projecting end of sleeve |36 is interiorly threaded as at |48 and inwardly thereof a plug |49 of rubber, cork or similar material is closely engaged with the sleeve wall and the end of the shaft ||8 to tightly seal the end of the sleeve and prevent the leakage of oil.

The brake drum |45 is securely held against axial movement on the sleeve |36 by means of a metal plug |50 the body of which has a tapered threaded bore and is diametrically split, as at ||l said plug body being also externally threaded for engagement with the internal threads |48 of the sleeve |36. One end of the plug is formed with a flange |52 for abutting contact with the outer end of the drum hub |46. After the split plug |50 is threaded home, to move the brake drum inwardly on the sleeve end to the position determined by the tapered splines |41 and simultaneously draw the sleeve and gear |38 outwardly to adjust the bearing, a tapered locking screw |53 is then threaded into the bore of the plug. This screw expands the split portions of the plug body and tightly locks the same with theI interiorly threaded end of the sleeve |36. Each brake drum |45 and the external brake mechanism cooperating therewith is enclosed within a housing |54 suitably secured to one of the side walls of the unit housing structure 41.

While any desired type of external brake applying mechanism might be employed, in Figure 4 of the drawings I have shown metal brake band sections 55 and |56 extending upwardly around opposite sides of drums |45 from the hinge or pivot connection |51 between their lower ends. Each of these metal band sections carries the usual brake lining material |58 on its inner face in opposed relation to the peripheral surface of the drum. At its upper end the meta'. band section |55 is connected by spaced metal straps |56 with the shaft |60 suitably journalled at its opposite ends in the walls of the housing structures 41 and |54. Between these straps a clevis member |6| is xed to the shaft |60 and extends upwardly therefrom. The axis of shaft |60 is located in a vertical plane which intersects the 10 axis of the brake drum |45 and in the upper ends of the spaced arms of the clevis |6| a pin |62 is loosely mounted at its opposite ends. This pin has a central opening diametrically therethrough receiving the upwardly extending rod |63 which is riveted, as at |64, to the upper end of the metal brake band section |56. The upper end of this rod is threaded and the nut |65 there-l on has bearing contact with the pin 62. A biasing spring |66 has one of its ends connected with rod |63 above the nut |65 while its other end is suitably attached to one of the walls of housing |54.

Externally of the housing |54 an upwardly extending arm |61 is suitably fixed to the projecting end of the shaft |60. The upper end of this arm is pivotally connected by a link |68 to the arm |69 extending downwardly from the shaft |10 mounted on the base of the turret housing 91 for the gear selecting mechanism and operated by the brake pedal |1|.

The spring |66 acts to normally retain the pin |62 in the position shown in Figure 4 with its axis spaced from one side of a vertical plane intersecting the axis of shaft |60 and with the liners |58 of the band sections |55 and |56 out of contact with the surface of the brake drum. When the brake pedal |1| is depressed the shaft |63 is rocked in a clockwise direction and pin |62 moved to a position on the opposite side of said vertical plane and spring |66 is stressed. Brake applying strain is thereby applied, through the rod |63, to the brake band sections and the liners |58 thereof are caused to engage and frictionally retard rotation of the drum |54 and the sleeve |36 and gear |31 connected to said drum. Preferably separate operating pedals are provided for the two brake mechanisms so that braking torque may be independently applied to the side gears of the differential as an aid in steering the vehicle.

The unit C of the assembly includes a housing |12 for the large speed reducing gears which arekeyed or splined to the inner ends of the driving axles |13 for the respective traction wheels of the vehicle. Preferably, casings |14 for said axles are integrally formed with the opposite side walls of the housing |12. As herein shown, each of the reducing gears has a cast iron hub, web and rim portion |15 and a hardened ring gear |16 is shrunk on the peripheral face of the rim portion and securely fixed in position at the contacting faces of said rim and gear by a plurality of spaced rivets, as indicated at |11.

The rear end of the transmission and difierential housing structure 41 is provided with a iiange |18 and draw-bar lugs 18 on the bottom wall thereof. The flange |18 provides means for properly locating the fiange of housing |12 so that said housing will be accurately positioned for the reception of the reducing gears through the open end of the housing structure 41 in meshed engagement with the respective sleeve gears |38 of the diierential. The mating flanges |18 and |80 are then securely connected by the bolts |8| and |82, the latter being relatively long and extending through boss-es |83 formed on the axle casings |14.

Each wheel axle |13 is supported in the inner and outer ends of the casing |14 by anti-friction roller bearings |84 and |85, respectively. If desired the axle casings may be provided with upper and lower integral re-inforcing ribs |14'. Nuts |13' threaded on the inner ends of the axles and engaged with the hubs of gears |16 11 provide means for properly adjusting the bearings |84 and |85, suitable locking washers ,being associated with said nuts. It will be noted that each axle casing |14 is of progressively decreasing external and internal diameter from its inner to its outer end. Thus oil collecting in the pocket |86 on the side wall oi housing |12 and draining into -the axle casing through duct |81 will be supplied to thegouter end axle bearing |85. Outwardly from said bearing the end of the axle casing is closed by an oil seal |88 which sur rounds the inner sleeve extension |90 of the traction wheel hub |89. The inner Wall of said sleeve and the periphery of the axle |13 'are provided with a plurality of mating longitudinal grooves to receive the pins |9| which are permanently connected by the welds |92, applied over the outer ends of said pins, to the wheel hub and axle. The hub |89 is preferably provided with a metal apron |93 suitably secured to the inner face thereof and having a cylindrical portion k|94 enclosing the outer end of the axle casing |14 to deflect dirt and prevent its entrance to the bearing |85. The metal wheel body, provided with the customary rim and traction lugs (not shown), is securely bolted to the outer face of the hub |89 in the usual manner.

Referring again to Figure 1 of the drawings, lubricating oil is supplied to the housing compartment 49 of unit B through the ller opening |93 and through opening 52 in the wall 48 to compartment 50, to maintain a normal oil bath level indicated by the line on the transmission, differential and speed reduction gearing. A trough |94 formed on the wall 48. within compartment 50, serves to keep the oil level on the transmission gears more or less constant during the operation of the differential and speed reduction gearing. as oil collecting in this trough will drain back into the compartment 49 through the bearing 51. The frontend wall of said compartment is also provided, above the power input shaft 56. with an oil collecting trough |95 from which oil is fed through registering openings |98 in said wall and the opposed wall of the housing 0 into the compartment thereof containing the power take-off gearing. Additional registering openings |91 vare formed through said walls to maintain the oil bath level 0 on said take-off gearing. Through the inclined duct |98 oil is supplied to the bearing 12' from the transmission gear compartment 49. At the rear lower end of the bottom wall of the housing structure 41, an oil drain opening is provided normallv closed by the plugr |99.

The side wall of gear compartment of the primarv unit A, opposite to the power take-oil shaft 3|, is provided with an opening 20| which receives actuating means for an accessory unit, This actuating means is carried by a casting 202 having an attaching flange 203 formed on one end of the housing 204 and secured to the wall of compartment by bolts'205 and 206. The latter bolt is relativelyY long for engagement through an opening in one end of a shaft 201 and registering openings in opposite sides of one of the bearing bosses 208 formed on the flange 203 at each side of the housing 204. Thus the shaft 201 is securely xed against axial or rotative movement relative to the casting 202.

In the present instance T have shown the accessory unit directlv mounted on the outer end of the housing 202 though it will be evident that, by employing suitable power transmitting connections, said unit may be mounted or arranged in more or less remote relation to the primary unit A. For the purpose of illustration, in Figures 2, 5 and 6 of the drawings, I have shown this accessory unit as comprising a well known type of hydraulic pump to be used for lifting the tractor implements and other purposes. 'I'he pump cylinders, generally indicated at 209, are vertically positioned andV integrally formed at their upper ends with a housing extension 2|0 for the plunger actuating bell cranks 2| The housing structure 2 I0 is formed with spaced bearing lugs 2|2, extending through the opening 2|3 in the front wall of housing 202, between which the bell cranks 2|| are fulcrumed upon the pin 2|4. One arm of each bell crank projects upwardly from pin 2 |4 and is provided with a can! engaging roller 2|5.

The actuating means for the bell cranks 2|| comprises a pair of reversely arranged cams 2|6, peripherally contacting the respective rollers 2|5 and secured on one end of a bearing race sleeve 2 |1 for unitary rotation therewith by the splines 2|8 externally formed on said sleeve. The cams are locked against relative sliding movement on the sleeve, with their hub portions in abutting contact by the snap rings 2|9 seated in notches 220 formed in the edges of the splines 2|8. The sleeve 2|1 is supported on the fixed shaft 201 by two cage type roller bearings 22| spaced apartby the sleeve 222 on said shaft and a hardened thrust Washer 223 surrounds the shaft 201 between each end of sleeve 2 |1 and one of the shaft bearings 208.

With the other end portion of the sleeve 2|1 ardriven gear 224 is connected by the splines 2|8 for sliding movement thereon and has a. grooved collar 225 formed on one side thereof to receive the arms of a shifting fork 228, whereby said gear may be shifted into and out of meshed engagement with the driving pinion 10 of the coupling sleeve 88 for the clutch and transmission input shafts.

Any preferred means may be employed for manually shifting the fork 228, but for this purpose I have herein shown a rod 221, supported for axial movement in suitable bearings 228 formed on the opposite side walls of the housing 202. The fork 22B has an end hub 229 securely fixed on the`rod 221 by a set screw 230. One of the bearings 228 is extended into the housing 202 and an opening 229 extends diametrically through one side of said bearing and the front wall of the housing. The rod 221 is formed on one side thereof with longitudinally spaced notches or seats 23|' for a latching member 23| which is yieldingly urged into engagement with the seat by a spring 232 in opening 229. The outer end of this opening is closed by an adjusting screw 233 engaged with the outer end of spring 232 to regulate the pressure of latching member 23| on seat 23| as required. The rod 221 is extended beyond one side of the housing 202 and a manually operable member 234 is suitably connected thereto.

From the above it will be readily seen that by moving the slide rod 221 in one direction fork 226 shifts the gear 224 to the left (Figure 2) on the sleeve 2|1 into mesh with the teeth of pinion 10, thus establishing a more or less direct driving connection between the clutch shaft |4 and the actuating cams 2|6, with maximum transmission of power to the accessory unit. The coupling sleeve 68 constitutes a common driving connection between the clutch shaft 4 and the transmission input shaft and the accessory actuating mechanism. Of course, movement of rod 221 and fork 226 in the opposite direction shifts the gear 13 224 to its idle position, as shown in the drawing, and in both positions of said gear the shifting means is held against casual or unintentional operation by the latching means 23|. The accessory actuating ymeans and its supporting casting 202 may be easily and quickly mounted in operative position on the housing structure of unit A or removed therefrom, when its use is not desired, and the side opening 20| in said housing structure closed by means of a suitable cover plate, replacing said casting.

It is to be noted that the power take-off means and the accessory actuating means are mounted on opposite sides of the housing I and, therefore, are located in balanced relation on opposide sides of the vehicle center line.l

The many advantages of my invention in practical tractor operation will be apparent to 'those familiar with the art. The arrangement of the transmission output shaft with its axis substantially coincident with the vehicle center line and in a common horizontal plane with the major shaft axis of the differential, and both of said shafts located a substantial distance below the wheel driving axles, results in a desirably low center of gravity, with increased stability of the organization as a whole, and minimum power transmission losses. Thus the potential driving energy of the motor will be applied in maximum degree to the final reducing gears directly fixed to the inner ends of the wheel axles. Also, by the removal of the final drive gearing from the wheels, large diameter wheels may be employed, resulting in better traction and the required clearance for crop rows and implements, notwithstanding the lowered center of gravity of the driving mechanism.

` By coupling the extension of transmission input shaft 58, which operates the pulley drive gearing to the clutch shaft I4 by means of sleeve i# closely adjacent to the clutch shaft bearing t5, the two bearings 51 and 58 provide adequate support for the pulley drive gear and the smooth transmission of power through the change-speed gearing to the power output shaft.

The selector mechanism above-described provides a simple and eficiently operating assembly of the gear shifting forks and operators shift lever with means for automatically locking the unshifted gears in idle position. washer 80, yieldingly resisting axial movement of the driven gears on the output shaft 1|, serves to obviate possible damage to the intermeshing gear teeth and to minimize noisy metallic chatter in the gear shifting operation.

It will further be noted that the various mechanisms are completely housed within three housing sections of simple and rugged construction which may be inexpensively fabricated. The section which receives the final reduction gears also embodies the wheel axle casings in a single unitary structure. These housing sections are provided with means which insures a proper and adequate supply of lubricant to the movable parts of the several mechanisms.

The differential construction and the means which I provide for rigidly securing the brake drums in connected relation with the side gears thereof enables the several parts to be easily and quickly assembled and installed as an operative unit in the train of driving mechanism.

In general, my invention, as herein disclosed,

' provides a practical farm tractor in which, in a relatively simple mechanical organization, power is efficiently transmitted from the engine or prime The spring assaoeo mover to the wheel axles. and has many'obviou's y* advantages in the planting or harvesting of farm crops. In additionl the machine also'embodies'- 4the other desirable features above referred to which materially increase its practical utility.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is thereforev tov be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and al1 changes which come withinthe meaning and range of equivalency of the claims are thereforeintended to be embraced therein.

What is claimed and desired to be securedby United States Letters Patent is:

l. In a motor vehicle driving mechanism, a housing having a front wall, an intermediate wall and a removable rear end wall', said intermediate wall dividing the housing into a forward transmission compartment and a rear. compartment containing in longitudinal succession a differential and final drive gearing for the axles, a longitudinally disposed transmission input shaft in the upper part of said transmission compartment mounted in bearings in said front and intermediate walls, a second housing secured to said front wall and having a wall therein defining an internal compartment adjacent said front wall, an engine driven shaft projecting into said internal compartment in alignment with said transmission input shaft, said transmission input shaft projecting through said front wall into said internal compartment, means for drive coupling said shafts together within said internal compartment, a drive gear for a power take-off shaft rigid with one of said shafts in. said second housing section, and a transmission output shaft in the lower part of said transmission compartment projecting through said intermediate wall into drive connection with said differential.

2.In the mechanism defined in claim 1, said transmission output shaft having its front end journalled in a bearing in said front wall and a passage in said front wall for supplying transmission lubricant to the front end of said bearing.

3. In motor vehicle driving mechanism. a housing having spaced apart walls forming a transmission compartment, transmission mechanism in said compartment including a transmission input shaft unsupported between said walls and anti-friction supporting bearing means for said shaft in each of said walls, an engine driven shaft, a power take-off drive gear housing forwardly of said transmission compartment, bearing means on said power take-off housing for said driven shaft, said transmission input shaft at one end extending exteriorly of said transmission compartment and into said power takeoff housing, a power take-off shaft mounted on the power take-off housing, gearing drive-connecting the extended end of the transmission input shaft with said power take-off shaft, a coupling sleeve connecting the driven shaft adjacent to said bearing means in aligned power transmitting relation with said input shaft, an accesl Number ential gearing in the respective compartments, said transmission gearing including a power input shaft in the upper part of said transmission compartment having one end projecting longitudinally through the adjacent end of said housing section,l a -second housing section xed to the latter end of said rst housing section and having an internal wall defining a gear compartment receiving the projecting end of the transmission inputshaft, an engine driven shaft projecting into said gear compartment, a sleeve in said gear compartment for coupling the driven shaft in axial alignment with the power input shaft, and a gear on said coupling sleeve.

5. In the mechanism dened in claim 4, a second gear mounted on said second housing section for rotation about an axis parallel to said engine driven shaft, and means for relatively shifting said gears into and out of mesh to drive said second gear directly from said engine driven shaft.

` BEVERLY W. KEESE.

REFERENCES CITED The following references are of record in the file o! this patent:

UNITED STATES PATENTS Name Datel 1,347,690 Ford July 27, 1920 1,419,240 Dunham June 13. 1922 Number Number 16 Name Date Keim Sept. 2, 1924 Johnston Nov. 3, 1925 Leake Nov. 3, 1925 Baia Dec. 21, 1926 Hamilton Nov. 5, 1929 Hamilton Mar. 15, 1932 Moree Apr. 5, 1932 Hendrickson Nov. 8.1932 Moree Apr. 3, 1934 Schoenrock Apr. 24, 1934 Johnston Nov. 27, 1934 Schoenrock Feb. 5. 1935 Harper Sept. 24, 1935 Ferguson Dec. 3, 1935 Bennett June 22, 1937 McCormick et al. Dec. 28, 1937 Baker et al Sept. 17, 1940 Strehlow June 3. 1941 Padgett June 10, 1941 Stumpf Mar. 10, 1942 Le Tourneau Apr. 20, 1943 Frudden Apr. 27, 1943 Eberhard June 1. 1943 AEberhard July 6, 1943 FOREIGN PATENTS Country Date Germany Dec. 10, 1928 

